Julius is giving a super-fast-talking pep speech to his gang members. You want to join in, but you have to be "canonized" first. This means the rest of the gang will be beating up on you. Ah, the fun.

LT RT punches
LB kicks
LT + RT blocks

Note that you can't use a weaopn even if you managed to get one before this mission, so it's really not worth it to work on that. You start with 1 enemy, then 2 more, then 2 more. If you punch / kick with good reflexes you should be able to win all the fights.

When you win, they're impressed with you. Apparently the only other guy to have done this was Johnny - the arrogant guy with glasses, neck tattoos and high hair.

It says Canonized mission complete. If you lose you still "pass" with $200, but if you win you get $1,000 cash.